<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <title>Title</title>
</head>
<body>

<div id="app">
  <h2>{{firstName + ' ' + lastName}}</h2>
  <h2>{{firstName}} {{lastName}}</h2>

  <h2>{{getFullName()}}</h2>

  <h2>{{fullName}}</h2>
</div>

<script src="../js/vue.js"></script>
<script>
  const app = new Vue({
    el: '#app',
    data: {
      firstName: 'Lebron',
      lastName: 'James'
    },
    // computed: 计算属性()
    computed: {
      fullName: function () {
        return this.firstName + ' ' + this.lastName
      }
    },
    methods: {
      getFullName() {
        return this.firstName + ' ' + this.lastName
      }
    }
  })
</script>

</body>
</html>